Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 684 insertions, 0 deletions

diff --git a/drivers/hid/hid-steelseries.c b/drivers/hid/hid-steelseries.c
new file mode 100644
index 000000000..7292da031
--- /dev/null
+++ b/drivers/hid/hid-steelseries.c
@@ -0,0 +1,684 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  HID driver for Steelseries devices
+ *
+ *  Copyright (c) 2013 Simon Wood
+ */
+
+/*
+ */
+
+#include <linux/device.h>
+#include <linux/dmi.h>
+#include <linux/hid.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/leds.h>
+#include <linux/led-class-multicolor.h>
+#include <linux/slab.h>
+
+#include "hid-ids.h"
+
+#define STEELSERIES_SRWS1		BIT(0)
+#define STEELSERIES_MSI_RGB		BIT(1)
+
+#define STEELSERIES_MSI_RGB_WVALUE 0x0300 /* Feature report, ID 0 */
+#define STEELSERIES_MSI_RGB_REPORT_LEN 524
+#define STEELSERIES_MSI_RGB_OPCODE 0x0c
+#define STEELSERIES_MSI_RGB_KLC_MODE 0x66
+#define STEELSERIES_MSI_RGB_ALC_MODE 0x06
+
+#define STEELSERIES_HAS_LEDS_MULTICOLOR \
+	(IS_BUILTIN(CONFIG_LEDS_CLASS_MULTICOLOR) || \
+	 (IS_MODULE(CONFIG_LEDS_CLASS_MULTICOLOR) && IS_MODULE(CONFIG_HID_STEELSERIES)))
+
+struct steelseries_device {
+	struct hid_device *hdev;
+	unsigned long quirks;
+
+#if STEELSERIES_HAS_LEDS_MULTICOLOR
+	struct led_classdev_mc mc_cdev;
+	struct mc_subled subled_info[3];
+	struct mutex rgb_lock; /* protects rgb_buf */
+	u8 *rgb_buf;
+#endif
+};
+
+#if IS_BUILTIN(CONFIG_LEDS_CLASS) || \
+    (IS_MODULE(CONFIG_LEDS_CLASS) && IS_MODULE(CONFIG_HID_STEELSERIES))
+#define SRWS1_NUMBER_LEDS 15
+struct steelseries_srws1_data {
+	__u16 led_state;
+	/* the last element is used for setting all leds simultaneously */
+	struct led_classdev *led[SRWS1_NUMBER_LEDS + 1];
+};
+#endif
+
+/* Fixed report descriptor for Steelseries SRW-S1 wheel controller
+ *
+ * The original descriptor hides the sensitivity and assists dials
+ * a custom vendor usage page. This inserts a patch to make them
+ * appear in the 'Generic Desktop' usage.
+ */
+
+static const __u8 steelseries_srws1_rdesc_fixed[] = {
+0x05, 0x01,         /*  Usage Page (Desktop)                */
+0x09, 0x08,         /*  Usage (MultiAxis), Changed          */
+0xA1, 0x01,         /*  Collection (Application),           */
+0xA1, 0x02,         /*      Collection (Logical),           */
+0x95, 0x01,         /*          Report Count (1),           */
+0x05, 0x01,         /* Changed  Usage Page (Desktop),       */
+0x09, 0x30,         /* Changed  Usage (X),                  */
+0x16, 0xF8, 0xF8,   /*          Logical Minimum (-1800),    */
+0x26, 0x08, 0x07,   /*          Logical Maximum (1800),     */
+0x65, 0x14,         /*          Unit (Degrees),             */
+0x55, 0x0F,         /*          Unit Exponent (15),         */
+0x75, 0x10,         /*          Report Size (16),           */
+0x81, 0x02,         /*          Input (Variable),           */
+0x09, 0x31,         /* Changed  Usage (Y),                  */
+0x15, 0x00,         /*          Logical Minimum (0),        */
+0x26, 0xFF, 0x03,   /*          Logical Maximum (1023),     */
+0x75, 0x0C,         /*          Report Size (12),           */
+0x81, 0x02,         /*          Input (Variable),           */
+0x09, 0x32,         /* Changed  Usage (Z),                  */
+0x15, 0x00,         /*          Logical Minimum (0),        */
+0x26, 0xFF, 0x03,   /*          Logical Maximum (1023),     */
+0x75, 0x0C,         /*          Report Size (12),           */
+0x81, 0x02,         /*          Input (Variable),           */
+0x05, 0x01,         /*          Usage Page (Desktop),       */
+0x09, 0x39,         /*          Usage (Hat Switch),         */
+0x25, 0x07,         /*          Logical Maximum (7),        */
+0x35, 0x00,         /*          Physical Minimum (0),       */
+0x46, 0x3B, 0x01,   /*          Physical Maximum (315),     */
+0x65, 0x14,         /*          Unit (Degrees),             */
+0x75, 0x04,         /*          Report Size (4),            */
+0x95, 0x01,         /*          Report Count (1),           */
+0x81, 0x02,         /*          Input (Variable),           */
+0x25, 0x01,         /*          Logical Maximum (1),        */
+0x45, 0x01,         /*          Physical Maximum (1),       */
+0x65, 0x00,         /*          Unit,                       */
+0x75, 0x01,         /*          Report Size (1),            */
+0x95, 0x03,         /*          Report Count (3),           */
+0x81, 0x01,         /*          Input (Constant),           */
+0x05, 0x09,         /*          Usage Page (Button),        */
+0x19, 0x01,         /*          Usage Minimum (01h),        */
+0x29, 0x11,         /*          Usage Maximum (11h),        */
+0x95, 0x11,         /*          Report Count (17),          */
+0x81, 0x02,         /*          Input (Variable),           */
+                    /*   ---- Dial patch starts here ----   */
+0x05, 0x01,         /*          Usage Page (Desktop),       */
+0x09, 0x33,         /*          Usage (RX),                 */
+0x75, 0x04,         /*          Report Size (4),            */
+0x95, 0x02,         /*          Report Count (2),           */
+0x15, 0x00,         /*          Logical Minimum (0),        */
+0x25, 0x0b,         /*          Logical Maximum (b),        */
+0x81, 0x02,         /*          Input (Variable),           */
+0x09, 0x35,         /*          Usage (RZ),                 */
+0x75, 0x04,         /*          Report Size (4),            */
+0x95, 0x01,         /*          Report Count (1),           */
+0x25, 0x03,         /*          Logical Maximum (3),        */
+0x81, 0x02,         /*          Input (Variable),           */
+                    /*    ---- Dial patch ends here ----    */
+0x06, 0x00, 0xFF,   /*          Usage Page (FF00h),         */
+0x09, 0x01,         /*          Usage (01h),                */
+0x75, 0x04,         /* Changed  Report Size (4),            */
+0x95, 0x0D,         /* Changed  Report Count (13),          */
+0x81, 0x02,         /*          Input (Variable),           */
+0xC0,               /*      End Collection,                 */
+0xA1, 0x02,         /*      Collection (Logical),           */
+0x09, 0x02,         /*          Usage (02h),                */
+0x75, 0x08,         /*          Report Size (8),            */
+0x95, 0x10,         /*          Report Count (16),          */
+0x91, 0x02,         /*          Output (Variable),          */
+0xC0,               /*      End Collection,                 */
+0xC0                /*  End Collection                      */
+};
+
+#if IS_BUILTIN(CONFIG_LEDS_CLASS) || \
+    (IS_MODULE(CONFIG_LEDS_CLASS) && IS_MODULE(CONFIG_HID_STEELSERIES))
+static void steelseries_srws1_set_leds(struct hid_device *hdev, __u16 leds)
+{
+	struct list_head *report_list = &hdev->report_enum[HID_OUTPUT_REPORT].report_list;
+	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
+	__s32 *value = report->field[0]->value;
+
+	value[0] = 0x40;
+	value[1] = leds & 0xFF;
+	value[2] = leds >> 8;
+	value[3] = 0x00;
+	value[4] = 0x00;
+	value[5] = 0x00;
+	value[6] = 0x00;
+	value[7] = 0x00;
+	value[8] = 0x00;
+	value[9] = 0x00;
+	value[10] = 0x00;
+	value[11] = 0x00;
+	value[12] = 0x00;
+	value[13] = 0x00;
+	value[14] = 0x00;
+	value[15] = 0x00;
+
+	hid_hw_request(hdev, report, HID_REQ_SET_REPORT);
+
+	/* Note: LED change does not show on device until the device is read/polled */
+}
+
+static void steelseries_srws1_led_all_set_brightness(struct led_classdev *led_cdev,
+			enum led_brightness value)
+{
+	struct device *dev = led_cdev->dev->parent;
+	struct hid_device *hid = to_hid_device(dev);
+	struct steelseries_srws1_data *drv_data = hid_get_drvdata(hid);
+
+	if (!drv_data) {
+		hid_err(hid, "Device data not found.");
+		return;
+	}
+
+	if (value == LED_OFF)
+		drv_data->led_state = 0;
+	else
+		drv_data->led_state = (1 << (SRWS1_NUMBER_LEDS + 1)) - 1;
+
+	steelseries_srws1_set_leds(hid, drv_data->led_state);
+}
+
+static enum led_brightness steelseries_srws1_led_all_get_brightness(struct led_classdev *led_cdev)
+{
+	struct device *dev = led_cdev->dev->parent;
+	struct hid_device *hid = to_hid_device(dev);
+	struct steelseries_srws1_data *drv_data;
+
+	drv_data = hid_get_drvdata(hid);
+
+	if (!drv_data) {
+		hid_err(hid, "Device data not found.");
+		return LED_OFF;
+	}
+
+	return (drv_data->led_state >> SRWS1_NUMBER_LEDS) ? LED_FULL : LED_OFF;
+}
+
+static void steelseries_srws1_led_set_brightness(struct led_classdev *led_cdev,
+			enum led_brightness value)
+{
+	struct device *dev = led_cdev->dev->parent;
+	struct hid_device *hid = to_hid_device(dev);
+	struct steelseries_srws1_data *drv_data = hid_get_drvdata(hid);
+	int i, state = 0;
+
+	if (!drv_data) {
+		hid_err(hid, "Device data not found.");
+		return;
+	}
+
+	for (i = 0; i < SRWS1_NUMBER_LEDS; i++) {
+		if (led_cdev != drv_data->led[i])
+			continue;
+
+		state = (drv_data->led_state >> i) & 1;
+		if (value == LED_OFF && state) {
+			drv_data->led_state &= ~(1 << i);
+			steelseries_srws1_set_leds(hid, drv_data->led_state);
+		} else if (value != LED_OFF && !state) {
+			drv_data->led_state |= 1 << i;
+			steelseries_srws1_set_leds(hid, drv_data->led_state);
+		}
+		break;
+	}
+}
+
+static enum led_brightness steelseries_srws1_led_get_brightness(struct led_classdev *led_cdev)
+{
+	struct device *dev = led_cdev->dev->parent;
+	struct hid_device *hid = to_hid_device(dev);
+	struct steelseries_srws1_data *drv_data;
+	int i, value = 0;
+
+	drv_data = hid_get_drvdata(hid);
+
+	if (!drv_data) {
+		hid_err(hid, "Device data not found.");
+		return LED_OFF;
+	}
+
+	for (i = 0; i < SRWS1_NUMBER_LEDS; i++)
+		if (led_cdev == drv_data->led[i]) {
+			value = (drv_data->led_state >> i) & 1;
+			break;
+		}
+
+	return value ? LED_FULL : LED_OFF;
+}
+
+static int steelseries_srws1_probe(struct hid_device *hdev,
+		const struct hid_device_id *id)
+{
+	int ret, i;
+	struct led_classdev *led;
+	struct steelseries_srws1_data *drv_data;
+	size_t name_sz;
+	char *name;
+
+	drv_data = devm_kzalloc(&hdev->dev, sizeof(*drv_data), GFP_KERNEL);
+	if (drv_data == NULL) {
+		hid_err(hdev, "can't alloc SRW-S1 memory\n");
+		return -ENOMEM;
+	}
+
+	hid_set_drvdata(hdev, drv_data);
+
+	ret = hid_parse(hdev);
+	if (ret) {
+		hid_err(hdev, "parse failed\n");
+		goto err;
+	}
+
+	if (!hid_validate_values(hdev, HID_OUTPUT_REPORT, 0, 0, 16)) {
+		ret = -ENODEV;
+		goto err;
+	}
+
+	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+	if (ret) {
+		hid_err(hdev, "hw start failed\n");
+		goto err;
+	}
+
+	/* register led subsystem */
+	drv_data->led_state = 0;
+	for (i = 0; i < SRWS1_NUMBER_LEDS + 1; i++)
+		drv_data->led[i] = NULL;
+
+	steelseries_srws1_set_leds(hdev, 0);
+
+	name_sz = strlen(hdev->uniq) + 16;
+
+	/* 'ALL', for setting all LEDs simultaneously */
+	led = devm_kzalloc(&hdev->dev, sizeof(struct led_classdev)+name_sz, GFP_KERNEL);
+	if (!led) {
+		hid_err(hdev, "can't allocate memory for LED ALL\n");
+		goto out;
+	}
+
+	name = (void *)(&led[1]);
+	snprintf(name, name_sz, "SRWS1::%s::RPMALL", hdev->uniq);
+	led->name = name;
+	led->brightness = 0;
+	led->max_brightness = 1;
+	led->brightness_get = steelseries_srws1_led_all_get_brightness;
+	led->brightness_set = steelseries_srws1_led_all_set_brightness;
+
+	drv_data->led[SRWS1_NUMBER_LEDS] = led;
+	ret = devm_led_classdev_register(&hdev->dev, led);
+	if (ret) {
+		hid_err(hdev, "failed to register LED %d. Aborting.\n", SRWS1_NUMBER_LEDS);
+		goto out; /* let the driver continue without LEDs */
+	}
+
+	/* Each individual LED */
+	for (i = 0; i < SRWS1_NUMBER_LEDS; i++) {
+		led = devm_kzalloc(&hdev->dev, sizeof(struct led_classdev)+name_sz, GFP_KERNEL);
+		if (!led) {
+			hid_err(hdev, "can't allocate memory for LED %d\n", i);
+			break;
+		}
+
+		name = (void *)(&led[1]);
+		snprintf(name, name_sz, "SRWS1::%s::RPM%d", hdev->uniq, i+1);
+		led->name = name;
+		led->brightness = 0;
+		led->max_brightness = 1;
+		led->brightness_get = steelseries_srws1_led_get_brightness;
+		led->brightness_set = steelseries_srws1_led_set_brightness;
+
+		drv_data->led[i] = led;
+		ret = devm_led_classdev_register(&hdev->dev, led);
+
+		if (ret) {
+			hid_err(hdev, "failed to register LED %d. Aborting.\n", i);
+			break;	/* but let the driver continue without LEDs */
+		}
+	}
+out:
+	return 0;
+err:
+	return ret;
+}
+#endif
+
+static const struct dmi_system_id steelseries_msi_rgb_dmi_table[] = {
+	{
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star International Co., Ltd."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Raider A18 HX A9WJG"),
+			DMI_MATCH(DMI_BOARD_NAME, "MS-182L"),
+		},
+	},
+	{ }
+};
+
+static struct usb_interface *steelseries_hid_to_usb_intf(struct hid_device *hdev)
+{
+	if (!hid_is_usb(hdev))
+		return NULL;
+
+	return to_usb_interface(hdev->dev.parent);
+}
+
+static bool steelseries_msi_rgb_is_interface0(struct hid_device *hdev)
+{
+	struct usb_interface *intf = steelseries_hid_to_usb_intf(hdev);
+	struct usb_device *udev;
+
+	if (!intf)
+		return false;
+
+	udev = interface_to_usbdev(intf);
+
+	return intf == usb_ifnum_to_if(udev, 0);
+}
+
+#if STEELSERIES_HAS_LEDS_MULTICOLOR
+
+static struct usb_device *steelseries_hid_to_usb_dev(struct hid_device *hdev)
+{
+	struct usb_interface *intf = steelseries_hid_to_usb_intf(hdev);
+
+	if (!intf)
+		return NULL;
+
+	return interface_to_usbdev(intf);
+}
+
+static int steelseries_msi_rgb_set_blocking(struct led_classdev *led_cdev,
+					    enum led_brightness brightness)
+{
+	struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(led_cdev);
+	struct steelseries_device *sd = container_of(mc_cdev,
+						    struct steelseries_device,
+						    mc_cdev);
+	struct hid_device *hdev = sd->hdev;
+	struct usb_device *udev = steelseries_hid_to_usb_dev(hdev);
+	int i, ret;
+	u8 r, g, b;
+
+	static const u8 keys[] = {
+		0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
+		0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13,
+		0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b,
+		0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23,
+		0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,
+		0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x33, 0x34,
+		0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c,
+		0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43, 0x44,
+		0x45, 0x46, 0x47, 0x49, 0x4b, 0x4c, 0x4e, 0x4f,
+		0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
+		0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
+		0x60, 0x61, 0x62, 0x63, 0x64, 0x66, 0xe0, 0xe1,
+		0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xf0
+	};
+	static const u8 alc_zones[] = { 0x00, 0x01, 0x02, 0x03 };
+
+	if (!udev)
+		return -ENODEV;
+
+	mutex_lock(&sd->rgb_lock);
+
+	led_mc_calc_color_components(mc_cdev, brightness);
+
+	r = mc_cdev->subled_info[0].brightness;
+	g = mc_cdev->subled_info[1].brightness;
+	b = mc_cdev->subled_info[2].brightness;
+
+	/*
+	 * Report layout (524 bytes):
+	 * Byte 0: Opcode (0x0c)
+	 * Byte 1: 0x00
+	 * Byte 2: Mode (0x66 for Keyboard, 0x06 for Lightbar)
+	 * Byte 3: 0x00
+	 * Bytes 4+: 4-byte chunks per LED (Index, R, G, B)
+	 */
+	memset(sd->rgb_buf, 0, STEELSERIES_MSI_RGB_REPORT_LEN);
+	sd->rgb_buf[0] = STEELSERIES_MSI_RGB_OPCODE;
+	sd->rgb_buf[1] = 0x00;
+	sd->rgb_buf[3] = 0x00;
+
+	for (i = 0; i < (STEELSERIES_MSI_RGB_REPORT_LEN - 4) / 4; i++)
+		sd->rgb_buf[4 + i * 4] = 0xff;
+
+	if (hdev->product == USB_DEVICE_ID_STEELSERIES_MSI_KLC) {
+		sd->rgb_buf[2] = STEELSERIES_MSI_RGB_KLC_MODE;
+		for (i = 0; i < ARRAY_SIZE(keys); i++) {
+			sd->rgb_buf[4 + i * 4] = keys[i];
+			sd->rgb_buf[5 + i * 4] = r;
+			sd->rgb_buf[6 + i * 4] = g;
+			sd->rgb_buf[7 + i * 4] = b;
+		}
+	} else {
+		sd->rgb_buf[2] = STEELSERIES_MSI_RGB_ALC_MODE;
+		for (i = 0; i < ARRAY_SIZE(alc_zones); i++) {
+			sd->rgb_buf[4 + i * 4] = alc_zones[i];
+			sd->rgb_buf[5 + i * 4] = r;
+			sd->rgb_buf[6 + i * 4] = g;
+			sd->rgb_buf[7 + i * 4] = b;
+		}
+	}
+
+	/*
+	 * Send the vendor report verbatim with usb_control_msg(): byte 0 is a
+	 * protocol opcode (0x0c), not a HID report ID, and the controller
+	 * expects it under report ID 0 (wValue 0x0300). hid_hw_raw_request()
+	 * would write the report number into byte 0, so the direct control
+	 * transfer is used to keep the payload byte-identical to the tested
+	 * userspace implementation.
+	 */
+	ret = hid_hw_power(hdev, PM_HINT_FULLON);
+	if (ret < 0)
+		goto out_unlock;
+
+	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+			      HID_REQ_SET_REPORT,
+			      USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+			      STEELSERIES_MSI_RGB_WVALUE, 0,
+			      sd->rgb_buf, STEELSERIES_MSI_RGB_REPORT_LEN,
+			      USB_CTRL_SET_TIMEOUT);
+
+	hid_hw_power(hdev, PM_HINT_NORMAL);
+
+out_unlock:
+	mutex_unlock(&sd->rgb_lock);
+	return ret < 0 ? ret : 0;
+}
+
+static void steelseries_msi_rgb_free_buf(void *data)
+{
+	kfree(data);
+}
+
+static int steelseries_msi_rgb_register(struct steelseries_device *sd)
+{
+	struct hid_device *hdev = sd->hdev;
+	struct led_classdev *led_cdev;
+	int ret;
+
+	sd->rgb_buf = kzalloc(STEELSERIES_MSI_RGB_REPORT_LEN, GFP_KERNEL);
+	if (!sd->rgb_buf)
+		return -ENOMEM;
+
+	ret = devm_add_action_or_reset(&hdev->dev,
+				       steelseries_msi_rgb_free_buf,
+				       sd->rgb_buf);
+	if (ret) {
+		sd->rgb_buf = NULL;
+		return ret;
+	}
+
+	ret = devm_mutex_init(&hdev->dev, &sd->rgb_lock);
+	if (ret) {
+		devm_remove_action(&hdev->dev, steelseries_msi_rgb_free_buf,
+				   sd->rgb_buf);
+		kfree(sd->rgb_buf);
+		sd->rgb_buf = NULL;
+		return ret;
+	}
+
+	sd->subled_info[0].color_index = LED_COLOR_ID_RED;
+	sd->subled_info[1].color_index = LED_COLOR_ID_GREEN;
+	sd->subled_info[2].color_index = LED_COLOR_ID_BLUE;
+	sd->subled_info[0].intensity = 255;
+	sd->subled_info[1].intensity = 255;
+	sd->subled_info[2].intensity = 255;
+	sd->subled_info[0].channel = 0;
+	sd->subled_info[1].channel = 1;
+	sd->subled_info[2].channel = 2;
+
+	sd->mc_cdev.subled_info = sd->subled_info;
+	sd->mc_cdev.num_colors = 3;
+
+	led_cdev = &sd->mc_cdev.led_cdev;
+	if (hdev->product == USB_DEVICE_ID_STEELSERIES_MSI_KLC)
+		led_cdev->name = "steelseries::kbd_backlight";
+	else
+		led_cdev->name = "steelseries::lightbar";
+
+	led_cdev->max_brightness = 255;
+	led_cdev->brightness_set_blocking = steelseries_msi_rgb_set_blocking;
+
+	ret = devm_led_classdev_multicolor_register(&hdev->dev, &sd->mc_cdev);
+	if (ret) {
+		devm_remove_action(&hdev->dev, steelseries_msi_rgb_free_buf,
+				   sd->rgb_buf);
+		kfree(sd->rgb_buf);
+		sd->rgb_buf = NULL;
+		return ret;
+	}
+
+	return 0;
+}
+#else
+static int steelseries_msi_rgb_register(struct steelseries_device *sd)
+{
+	return -ENODEV;
+}
+#endif
+
+static int steelseries_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+	struct steelseries_device *sd;
+	int ret;
+
+	if (hdev->product == USB_DEVICE_ID_STEELSERIES_SRWS1) {
+#if IS_BUILTIN(CONFIG_LEDS_CLASS) || \
+    (IS_MODULE(CONFIG_LEDS_CLASS) && IS_MODULE(CONFIG_HID_STEELSERIES))
+		return steelseries_srws1_probe(hdev, id);
+#else
+		return -ENODEV;
+#endif
+	}
+
+	sd = devm_kzalloc(&hdev->dev, sizeof(*sd), GFP_KERNEL);
+	if (!sd)
+		return -ENOMEM;
+	hid_set_drvdata(hdev, sd);
+	sd->hdev = hdev;
+	sd->quirks = id->driver_data;
+
+	if (sd->quirks & STEELSERIES_MSI_RGB) {
+		if (!dmi_check_system(steelseries_msi_rgb_dmi_table) ||
+		    !steelseries_msi_rgb_is_interface0(hdev)) {
+			hid_dbg(hdev, "MSI RGB quirk not applicable, using generic HID path\n");
+			sd->quirks &= ~STEELSERIES_MSI_RGB;
+		}
+	}
+
+	ret = hid_parse(hdev);
+	if (ret)
+		return ret;
+
+	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+	if (ret)
+		return ret;
+
+	ret = hid_hw_open(hdev);
+	if (ret)
+		goto err_stop;
+
+	if (sd->quirks & STEELSERIES_MSI_RGB) {
+		ret = steelseries_msi_rgb_register(sd);
+		if (ret) {
+			hid_warn(hdev,
+				 "Failed to register MSI RGB LEDs: %d, continuing without RGB support\n",
+				 ret);
+			sd->quirks &= ~STEELSERIES_MSI_RGB;
+		}
+	}
+
+	return 0;
+
+err_stop:
+	hid_hw_stop(hdev);
+	return ret;
+}
+
+static void steelseries_remove(struct hid_device *hdev)
+{
+	if (hdev->product == USB_DEVICE_ID_STEELSERIES_SRWS1) {
+#if IS_BUILTIN(CONFIG_LEDS_CLASS) || \
+    (IS_MODULE(CONFIG_LEDS_CLASS) && IS_MODULE(CONFIG_HID_STEELSERIES))
+		hid_hw_stop(hdev);
+#endif
+		return;
+	}
+
+	hid_hw_close(hdev);
+	hid_hw_stop(hdev);
+}
+
+static const __u8 *steelseries_srws1_report_fixup(struct hid_device *hdev,
+		__u8 *rdesc, unsigned int *rsize)
+{
+	if (hdev->vendor != USB_VENDOR_ID_STEELSERIES ||
+	    hdev->product != USB_DEVICE_ID_STEELSERIES_SRWS1)
+		return rdesc;
+
+	if (*rsize >= 115 && rdesc[11] == 0x02 && rdesc[13] == 0xc8
+			&& rdesc[29] == 0xbb && rdesc[40] == 0xc5) {
+		hid_info(hdev, "Fixing up Steelseries SRW-S1 report descriptor\n");
+		*rsize = sizeof(steelseries_srws1_rdesc_fixed);
+		return steelseries_srws1_rdesc_fixed;
+	}
+	return rdesc;
+}
+
+static const struct hid_device_id steelseries_devices[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_STEELSERIES, USB_DEVICE_ID_STEELSERIES_SRWS1),
+	  .driver_data = STEELSERIES_SRWS1 },
+
+#if STEELSERIES_HAS_LEDS_MULTICOLOR
+	{ /* MSI Raider A18 KLC */
+	  HID_USB_DEVICE(USB_VENDOR_ID_STEELSERIES, USB_DEVICE_ID_STEELSERIES_MSI_KLC),
+	  .driver_data = STEELSERIES_MSI_RGB },
+
+	{ /* MSI Raider A18 ALC */
+	  HID_USB_DEVICE(USB_VENDOR_ID_STEELSERIES, USB_DEVICE_ID_STEELSERIES_MSI_ALC),
+	  .driver_data = STEELSERIES_MSI_RGB },
+#endif
+
+	{ }
+};
+MODULE_DEVICE_TABLE(hid, steelseries_devices);
+
+static struct hid_driver steelseries_driver = {
+	.name = "steelseries",
+	.id_table = steelseries_devices,
+	.probe = steelseries_probe,
+	.remove = steelseries_remove,
+	.report_fixup = steelseries_srws1_report_fixup,
+};
+
+module_hid_driver(steelseries_driver);
+MODULE_DESCRIPTION("HID driver for Steelseries devices");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Simon Wood <simon@mungewell.org>");